1. Field of the Invention
The present invention relates to an apparatus for lifting materials. In particular, the present invention relates to an apparatus for lifting sheets of material so that they may be placed in another desired location.
2. Background of the Invention
There are a variety of situations in which a person must handle large pieces of steel or other materials and move them from one location to another. One prime example is materials which are used during construction. If a pipeline needs to be laid under a road, it is usually required to cut the road surface in order to lay the pipe. Because the road surface has been cut, the road must either be closed to traffic, or something must be placed over the opening to provide a surface over which cars and pedestrians can travel. This is often accomplished by covering the opening with a steel plate. The width of the opening will typically determine the thickness of the place. For example, in California a 1″ steel plate may be used to cover an opening which is no greater than 42 inches while a 1½″ plate can cover an opening up to 96 inches.
Additionally, plates can also be used to shore the sidewalls of trenches. When a trench is dug, there is a risk that the sidewalls will collapse into the void. Each year construction workers are injured and killed when the walls collapse, burying the worker. Because of this, state and federal regulatory agencies require that any trench deeper than 3 feet be properly shored. In some environments, this done by placing a frame in the trench and then inserting sheets of material between the frame and the sidewalls of the trench to prevent the trench walls from collapsing.
Regardless of the use to which the plates of material are put, handling large pieces of steel or other material can be difficult and dangerous. The plates will often weigh several hundred pounds. Thus, it is important to handle the plates properly. At the same time, it is important to have the plates of material be easy to handle to improve efficiency in placement and removal of the plates.
It will be appreciated that the drawings are illustrative and not limiting of the scope of the invention which is defined by the appended claims. The embodiments shown accomplish various aspects and objects of the invention. It will be appreciated that may not be possible to clearly show each element and aspect of the present disclosure in a single figure, and as such, multiple figures are presented to separately illustrate the various details of different aspects of the invention in greater clarity. Similarly, not all configurations or embodiments described herein or covered by the appended claims will include all of the aspects of the present disclosure as discussed above.